Analysis of nueroparalytic keratitics using coculture system of neural and corneal epithelial cells

利用胶原玻璃体膜共培养系统，研究了神经细胞对人角膜上皮细胞（HCE）的影响。我们发现，神经细胞的存在促进了HCE细胞的分层，并上调了连接蛋白n -钙粘蛋白的表达。神经细胞的这些作用由分化的PC12细胞或三叉神经细胞释放的神经肽（P物质和CGRP）制备的条件培养基模拟。此外，这些神经肽的拮抗剂抑制了三叉神经细胞对HCE细胞分层和n -钙粘蛋白表达的刺激作用。因此，我们的研究结果表明，三叉神经细胞释放的神经肽上调了N-cadherin在角膜上皮细胞中的表达，并促进了角膜上皮细胞的分层，这表明三叉神经细胞可能在维持角膜稳态和修复角膜损伤中发挥重要作用。

With the use of a coculture system based on a collagen vitrigel membrane, we have investigated the effects of neural cells on human corneal epithelial (HCE) cells. We found that the presence of neural cells promoted the stratification of HCE cells as well as up-regulated expression of the junction protein N-cadherin. These effects of neural cells were mimicked by conditioned medium prepared from differentiating PC12 cells or by neuropeptides (substance P and CGRP) released from trigeminal nerve cells. Furthermore, antagonists of these neuropeptides inhibited the stimulatory effects of trigeminal neurons on the stratification of and N-cadherin expression by HCE cells. Our results thus indicate that neuropeptides released from trigeminal neurons up-regulate N-cadherin expression in and promote the stratification of corneal epithelial cells, and they therefore suggest that such neurons may play an important role in the maintenance of corneal homeostasis and repair of corneal damage.